On the introduction of EJB learning the history of-EJB technology

Greennetboyapril 09,2005 article content 1. What is the EJB2.EJB generation of 3.EJB development prospects for 4.EJB (1) What is EJBEJB is the abbreviation of Enterprise JavaBeans, is the main distributed component model for generating business applications. Specifically, EJB separates business logic implementations from system-level services, allowing developers to focus on the business issues at hand. Technically, EJB is the specification of the Java server-side service framework, It describes the problems that need to be solved when building components, such as extensible (scalable), distributed (distributed), transaction processing (transcational), data storage (persistent), security. EJB Technology defines a reusable set of components that programmers can use to build Java-based distributed applications like building blocks (2) EJB generation at the beginning of 1998, Sun launched the Enterprise JavaBeans (EJB) specification for the first time, In the past 7 years, EJB has been well popularized and developed. And after several versions evolve, now the highest version has reached EJB3.0, for more information on EJB3.0 please check http://www.java.net/cs/user/forum/cs_disc/1838, This online discussion discusses in detail the new features of the EJB3.0 specification. Interested in the past to see, but are English, may be a little difficult to understand. (3) The development of EJB before the advent of personal computers in the the 1980s, computing systems were typically a large centralized, decentralized system consisting of dumb terminals connecting mainframes. The PC does not change the computational model, only the processing functions are transferred to the user's desktop, and the various components of the application are put together, including the data and user interface. This monolithic application cannot be shared among users. In the late 20th century, there was a client/server system that was very large, after years of development, This two-tier architecture is already unable to meet the requirements, resulting in the current popular three-tier architecture and N-tier architecture, and with the development of object-oriented, this distributed application has been a lot of development space, EJB as a middleware technology to meet this development needs, And with strong scalability and security, EJB and Java EE are known as the most mature and sound enterprise development models and play an irreplaceable role in developing large, secure, scalable, scalable, and transactional systems. It is because of this importance and the complexity of EJB, The developers of EJBS are also more likely to pay than others. It's like a family of "scary paychecks" that Csdn once said. (4) The development foreground of EJB the advantages of EJB have been more thanIn more detail, what is the prospect of its development? EJBs and COM COM + + are both pros and cons, although in the past few years, the EJB has been well developed, but the latest hibernate and spring technology, due to great flexibility and simplicity, the emergence of EJB vs SPRING,EJB vs Hibernate's phenomenon, EJB3.0 's release is also meant to make EJB survive and develop further in these confrontations. But anyway, EJB as a technical specification, in the future for a long time will not lose its original design characteristics, It will not disappear because of the emergence of a new technology, so in general, EJB still has a very good development space. I hope I just started learning EJB and netizens should be confident to learn this technical Reference: <<EJB Programming Guide >> (US) Faiz Arni, etc. Electronics Publishing House